Control method and control device for touch sensor panel

ABSTRACT

A control method for a touch sensor panel is disclosed. The method includes obtaining touch information on the touch sensor panel from which an electrical signal outputted is changed according to a touch; detecting at least one valid touch from the touch information; determining that a valid touch of the at least one valid touch is included in a palm touch group by (a) detecting a palm touch (e.g., which meets a palm touch condition) among the at least one valid touch, and (b) determining valid touches (e.g., all valid touches) from a detection time of the palm touch to a predetermined backward tracking time; and non-displaying, on a display unit, the valid touch included in the palm touch group.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/911,934, filed Mar. 5, 2018, which is a continuation of U.S. patentapplication Ser. No. 14/734,208, filed Jun. 9, 2015, which claimspriority under 35 U.S.C. § 119 to Korean Patent Application No.:10-2014-0070096, filed Jun. 10, 2014. The disclosures of theaforementioned priority applications are incorporated herein byreference in their entirety.

FIELD OF THE INVENTION

The present invention relates to a control method and a control devicefor a touch sensor panel, and more particularly to a method foridentifying and removing a palm touch on the touch sensor panel and acontrol device of the touch sensor panel, which performs the same.

BACKGROUND OF THE INVENTION

A touch sensor panel is a device for inputting information by performinga touch operation (hereafter, referred to as touch) on a character orparticular position displayed on a screen through use of an object likea user's finger or stylus pen without using an input device like akeyboard or mouse. The touch sensor panel can be used in variousconfigurations such as electronic devices including a personal dataassistant (PDA) and a portable terminal, a variety of electronicproducts, an automatic teller machine, etc.

For example, the touch sensor panel is a transparent panel including atouch-sensitive surface and may configure a touch screen by beingattached to the front side, etc., of a display panel. As such, the touchsensor panel is used together with the display panel, etc., and thus,can be used as an interactive graphic input device which allows the userto designate a position by himself/herself while watching the screen.

In particular, when the user draws or writes by touching the touchsensor panel through the object like the stylus pen or finger, it isquite probable that a touch by palm other than the object is erroneouslyregarded as an input action. Therefore, research is being conducted toexclude the touch by palm from a touch input on the touch sensor panel.

SUMMARY OF THE INVENTION

In an embodiment, a control method for a touch sensor panel isdisclosed. The method includes obtaining touch information on the touchsensor panel from which an electrical signal outputted is changedaccording to a touch; detecting at least one valid touch from the touchinformation; determining that a valid touch of the at least one validtouch is included in a palm touch group by (a) detecting a palm touch(e.g., which meets a palm touch condition) among the at least one validtouch, and (b) determining valid touches (e.g., all valid touches) froma detection time of the palm touch to a predetermined backward trackingtime; and non-displaying, on a display unit, the valid touch included inthe palm touch group.

In an embodiment, a control method for a touch sensor panel isdisclosed, the method comprising obtaining touch information on thetouch sensor panel from which an electrical signal outputted is changedaccording to a touch; detecting at least one valid touch from the touchinformation; determining that a valid touch of the at least one validtouch is included in a palm touch group by (a) detecting a palm touch,which meets a palm touch condition, among the at least one valid touch,and (b) determining that the detected palm touch and the valid touchoccur within a predetermined time period; and displaying, on a displayunit, an input corresponding to each of the at least one valid touchother than the valid touch included in the palm touch group.

In an embodiment, a control device of a touch sensor panel is disclosed,the control device comprising a touch information detector which obtainstouch information on the touch sensor panel from which an electricalsignal outputted is changed according to a touch; a processor whichdetects at least one valid touch from the touch information anddetermines that a valid touch of the at least one valid touch isincluded in a palm touch group by (a) detecting a palm touch, whichmeets a palm touch condition, among the at least one valid touch, and(b) determining that the detected palm touch and the valid touch occurswithin a predetermined time period; and a controller configured to causea display unit to display an input corresponding to each of the at leastone valid touch other than the valid touch included in the palm touchgroup.

An embodiment is a method for controlling a touch sensor panel accordingto an embodiment of the present invention. The control method includes:obtaining touch information on the touch on the touch sensor panel fromwhich an electrical signal outputted is changed according to a touch;detecting at least one valid touch from the touch information;determining the valid touch which is included in a palm touch groupamong the at least one valid touch; and displaying an inputcorresponding to the valid touch other than the valid touch which isincluded in the palm touch group among the at least one valid touch, ona display unit.

An embodiment is a control device of the touch sensor panel according tothe embodiment of the present invention. The control device includes: atouch information detector which obtains touch information on the touchsensor panel from which an electrical signal outputted is changedaccording to a touch; a processor which detects at least one valid touchfrom the touch information and determines the valid touch which isincluded in a palm touch group among the at least one valid touch; and acontroller which causes a display unit to display an input correspondingto the valid touch other than the valid touch which is included in thepalm touch group among the at least one valid touch.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view for describing a palm touch in an apparatus including atouch sensor panel according to an embodiment of the present invention;

FIG. 2 is a flowchart showing a method for removing the palm touch inthe touch sensor panel according to the embodiment of the presentinvention;

FIG. 3 is a structure view showing the apparatus including the touchsensor panel according to the embodiment of the present invention;

FIG. 4 shows an example of the touch sensor panel according to theembodiment of the present invention; and

FIG. 5 is a view for describing (a) a backward tracking method and (b) aforward tracking method in the method for removing the palm touch inaccordance with the embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description of the present invention shows aspecified embodiment of the present invention and will be provided withreference to the accompanying drawings. The embodiment will be describedin enough detail that those skilled in the art are able to embody thepresent invention. It should be understood that various embodiments ofthe present invention are different from each other and need not bemutually exclusive. For example, a specific shape, structure andproperties, which are described in this disclosure, may be implementedin other embodiments without departing from the spirit and scope of thepresent invention with respect to one embodiment. Also, it should benoted that positions or placements of individual components within eachdisclosed embodiment may be changed without departing from the spiritand scope of the present invention. Similar reference numerals in thedrawings designate the same or similar functions in many aspects.

Hereafter, in an apparatus 1000 including a touch sensor panel accordingto an embodiment of the present invention, a method for removing and/oridentifying a palm touch and a control device 800 performing the samewill be described with reference to the accompanying drawings.

FIG. 1 is a view for describing the palm touch in the apparatusincluding the touch sensor panel according to the embodiment of thepresent invention. In the apparatus 1000 including the touch sensorpanel of FIG. 1, an example is shown where a touch screen is configuredby attaching the touch sensor panel 100 to a display panel constitutinga display unit 300. Therefore, a user can perform a touch inputoperation by directly touching the screen of the display unit 300. Suchan input action can be directly displayed on the screen of the displayunit 300.

FIG. 1 shows that the input on the touch sensor panel 100 by a touch ofan object 10 is displayed on the display unit 300. Here, a stylus pen isused as an example of the object 10. A portion 310 of the screen of thedisplay unit 300 of FIG. 1 shows that the stylus pen has been selectedas a touch object through an icon 311. An action corresponding to theinput by the touch of the object 10 may be displaying a positioncorresponding to the touch on the display unit 300. Therefore, inaccordance with the movement of the object 10 on the touch surface ofthe touch sensor panel 100, the movement of the touch may be, as shownin FIG. 1, tracked and displayed on the display unit 300.

Here, as shown in FIG. 1, when a touch is input by the object 10, user'shand 20 holding the object 10 may touch the touch sensor panel 100.Here, this touch of the user may be also determined as a touch input andbe displayed on the display unit 300. However, this touch is notintended by the user, and thus, needs to be prevented from beingdisplayed on the display unit 300.

When the user touches the touch sensor panel 100 with the object 10, theuser should be careful not to allow other things other than the object10 to touch the touch sensor panel 100. However, when the user performsa delicate work such as drawing, writing, etc., on the touch sensorpanel 100, the accuracy of the touch input may be deteriorated or wristfatigue of the user may be increased by long-term input action.

Therefore, the embodiment of the present invention provides a method foridentifying/removing the palm touch such that the palm touch can beexcluded from the touch input even when the user's hand, particularly,the palm of the user touches the touch sensor panel 100 in the user'stouch on the touch sensor panel 100 through the object 10. The methodfor identifying/removing the palm touch and the control device 800 ofthe touch sensor panel 100 which performs the same in accordance withthe embodiment of the present invention will be described in detail withreference to FIGS. 2 to 5.

FIG. 2 is a flowchart showing the method for removing the palm touch inapparatus 1000 including the touch sensor panel according to theembodiment of the present invention. As shown in FIG. 2, the method mayinclude obtaining touch information based on the touch on the touchsensor panel 100 from which an electrical signal outputted is changedaccording to the touch (S810); detecting at least one valid touch fromthe touch information (S820); determining the valid touch which isincluded in a palm touch group among the at least one valid touch(S840); and displaying the input corresponding to the valid touch otherthan the valid touch which is included in the palm touch group among theat least one valid touch, on the display unit (S830 and S850).

The method shown in FIG. 2 for removing the palm touch in accordancewith the embodiment of the present invention will be described in detailwith reference to the apparatus 1000 which includes the touch sensorpanel 100 performing the same.

First, the apparatus 1000 including the touch sensor panel 100 accordingto the embodiment of the present invention will be briefly described.FIG. 3 is a structure view showing the apparatus including the touchsensor panel according to the embodiment of the present invention. Theapparatus 1000 according to the embodiment of the present invention mayinclude the touch screen 100 and the control device 800 of the touchsensor panel 100.

The apparatus 1000 including the touch sensor panel 100 according to theembodiment of the present invention may be a portable electronic devicesuch as a laptop computer, a personal digital assistant (PDA), and asmart phone. Also, apparatus 1000 according to the embodiment of thepresent invention may be a non-portable electronic device such as adesktop computer, and a smart television.

The apparatus 1000 including the touch sensor panel 100 according to theembodiment of the present invention may include the touch sensor panel100 and the display unit 300. The touch sensor panel 100 according tothe embodiment of the present invention may be configured to form thetouch screen by being attached to the display unit 300. It can beconsidered that the touch sensor panel 100 and the display unit 300 areseparated from each other. It is enough as long as the touch input onthe touch sensor panel 100 is displayed on the display unit 300. Thedisplay unit 300 according to the embodiment of the present inventionmay include, for example, the display panel. The display unit 300includes a screen allowing the user to visually check the contentsdisplayed on the display unit. Here, the display unit 300 may be drivenby a driver which causes the contents to be displayed on the displayunit 300.

The touch sensor panel 100 according to the embodiment of the presentinvention allows the user to operate a computing system by simplytouching the touch sensor panel 100 with the object, i.e., a finger,etc. In general, the touch sensor panel 100 recognizes the touch andtouch position thereon, and then the computing system analyzes the touchand performs operations in accordance with the analysis.

Since the electrical signal which is output is changed by the touch onthe touch sensor panel 100, the touch sensor panel 100 according to theembodiment of the present invention is configured to detect whether ornot and where the touch has occurred on the touch sensor panel 100.Also, the touch sensor panel 100 according to the embodiment of thepresent invention may be configured to detect the magnitude of the touchpressure when the touch occurs on the touch sensor panel 100. The touchsensor panel 100 may include any panel which is configured to detectwhether or not the touch has occurred, the touch position and/or touchpressure when the touch occurs on the touch sensor panel 100. Also, thetouch sensor panel 100 may be any panel which is configured to detectthe size of a touched region including a node where a drive line and asensing line have crossed each other when the touch occurs on the touchsensor panel 100. For example, the touch sensor panel 100 has acapacitive type in which the touch information is obtained from thechange of capacitance by the touch, a resistive type in which the touchinformation is obtained from the change of resistance by the touch, aninfrared type in which the touch information of the touch object isobtained by flowing infrared rays on the touch sensor panel 100 in up,down, right and left directions, and a pressure type in which the touchinformation is detected by the force distribution through a pressuresensor when a pressure is applied to the touch sensor panel 100, etc.Additionally, it is clear to those skilled in the art that any methodcan be applied as long as it is possible to detect whether or not thetouch has occurred, touch position, touch pressure and/or the size ofthe touch region.

Hereafter, the configuration and operation of the touch sensor panel 100according to the embodiment of the present invention will be brieflydescribed by taking the capacitive type touch sensor panel an examplethereof. However, the method for controlling the touch sensor panel 100according to the embodiment of the present invention, that is, themethod for identifying/removing the palm touch is not limited to thecapacitive type touch sensor panel and can be applied to various typetouch sensor panels 100.

FIG. 4 shows an example of the capacitive type touch sensor panel 100according to the embodiment of the present invention. Referring to FIG.4, the touch sensor panel 100 may include a plurality of drive lines TX1to TXn arranged in a first direction, a plurality of sensing lines RX1to RXm arranged to cross the drive lines TX1 to TXn, and a plurality ofsensing cells “A” and “B” formed at the node, i.e., the crossings of thedrive lines TX1 to TXn and the sensing line RX1 to RXm. Here, althoughit is shown that the plurality of drive lines TX1 to TXn and theplurality of sensing lines RX1 to RXm are arranged to cross each otherin the form of an orthogonal coordinate, this is just an embodiment.They may be also arranged to cross in the form of other geometricalstructures (a concentric line and a radial line of a polar coordinatearrangement), etc. Also, the plurality of drive lines TX1 to TXn and theplurality of sensing lines RX1 to RXm may be disposed on the same plane.Also, an insulation layer (not shown) functioning as a dielectricmaterial may be formed between the plurality of the drive lines TX1 toTXn and the plurality of the sensing lines RX1 to RXm.

The plurality of drive lines TX1 to TXn and the plurality of sensinglines RX1 to RXm may be formed on a transparent substrate (not shown).The drive lines and the sensing lines may be made of a transparentconductive material. Here, the transparent conductive material may beformed of indium-tin-oxide (ITO), indium-zinc-oxide (IZO) or carbon nanotube (CNT). Also, the plurality of drive lines TX1 to TXn and theplurality of sensing lines RX1 to RXm may be formed of a metal mesh ornano silver material.

When the object touches the touch sensor panel 100 formed as describedabove, the capacitances of the sensing cells “A” and “B” located at thetouch position of the touch sensor panel 100 are changed, so that thetouch sensor panel 100 can generate a touch signal which corresponds tothe change of the capacitance.

The apparatus 1000 including the touch sensor panel 100 according to theembodiment of the present invention may further include a driver 200which applies a driving signal to the drive lines TX1 to TXn of thetouch sensor panel 100, and a touch information detector 400 whichreceives a signal including information on a capacitance formed betweenthe drive lines TX1 to TXn and the sensing lines RX1 to RXm by applyingthe driving signal. Here, the driver 200 is not shown in FIG. 3.However, the driver 200 can be included in the control device 800 of thetouch sensor panel 100 according to the embodiment of the presentinvention.

When the object like a finger or a stylus pen approaches close to thetouch sensor panel 100, the value of the capacitance may be changed. Thetouch information detector 400 senses such electrical characteristics,and thus, can detect whether or not and/or where the touch has occurredon the touch sensor panel 100. For example, the touch informationdetector 400 can detect whether or not the touch has occurred on thetouch sensor panel 100 and the touch position in a two-dimensional planecomposed of a first axis and a second axis.

More specifically, when the touch occurs on the touch sensor panel 100,the drive line TX to which the driving signal has been applied, so thata second directional position of the touch can be detected. In the samemanner, when the touch occurs on the touch sensor panel 100, thecapacitance change is detected from the sensing signal received throughthe sensing line RX, so that a first directional position of the touchcan be detected.

The touch information detector 400 according to the embodiment of thepresent invention may perform the obtaining the touch information (S810)of FIG. 2. The touch information detector 400 processes the sensingsignal received from the sensing lines RX of the touch sensor panel 100,and thus, can obtain a coordinate value as well as a capacitance changeamount due to the touch. The touch information according to theembodiment of the present invention may include the change amount of thereceived sensing signal (or capacitance change amount) and/orinformation on the coordinate on the touch sensor panel 100 where thischange has occurred. The touch information detector 400 according to theembodiment of the present invention may be implemented by a touchsensing integrated circuit (IC). Here, the driver 200 can be alsointegrated on the same touch sensing IC in accordance with theembodiment of the present invention.

The detecting at least one valid touch by using the touch informationobtained by the touch information detector 400 (S820) may be performed.In the embodiment of the present invention, the detecting the validtouch (S820) may be performed by a processor 500. For example, a firstprocessing unit 510 of the processor 500 can detect whether or not theinvalid touch has occurred on the touch sensor panel 100. For example,the first processing unit 510 can determine that the valid touch hasoccurred only when the capacitance change amount is greater than apredetermined reference value in the coordinate where the capacitancehas changed.

Here, the predetermined reference value intends to prevent the change ofa meaningless sensing signal from being recognized as a touch input by asignal error due to noise. This valid touch may include not only thedirect touch on the touch sensor panel 100 but also hovering satisfyinga predetermined condition. Here, the predetermined reference value maybe changed according to the accuracy necessary for the embodiment,environment for embodiments, etc., and can be obtained throughexperiments. The predetermined reference value may be stored in a memory600 shown in FIG. 3.

Here, one or more detected valid touch may occur at the same time or atmutually different times. The apparatus 1000 including the touch sensorpanel 100 according to the embodiment of the present invention canrecognize a plurality of simultaneous touches.

The processor 500 of the apparatus 1000 according to the embodiment ofthe present invention can perform the determining the valid touch whichis included in the palm touch group among the at least one valid touch(S840). A second processing unit 520 included in the processor 500 shownin FIG. 3 can perform the above-described S840.

The apparatus 1000 according to the embodiment of the present inventionmay further include a controller 700 which causes the display unit 300to perform the displaying the input corresponding to the valid touchother than the valid touch which is included in the palm touch groupamong the at least one valid touch, on the display unit (S830 and S850).

Hereafter, the determining the valid touch which is included in the palmtouch group among the at least one valid touch (S840) will be described.

In the method for identifying/removing the palm touch in accordance withthe embodiment of the present invention, the valid touch detected inS820 may be stored in the memory 600 according to the touch order(S841). The coordinates of the valid touch and/or time of the validtouch as well as the valid touch may be stored in the memory 600. Also,the sensing signal and/or value of the capacitance change by the validtouch can be stored. Here, the valid touch which is stored according tothe embodiment may include a touch occurring during a predetermined timeperiod before the present time point. A touch occurring outside of thepredetermined time period may be deleted from the memory 600. Here, thepredetermined time period may be set greater than a period of a backwardtracking time T_(BT) to be described below.

The second processing unit 520 determines whether each valid touch meetsa palm touch condition or not. The second processing unit 520 canperform detecting the valid touch satisfying the palm touch condition asa palm touch (S842).

The palm touch condition may be stored in the form of a firmware in thememory 600 by default. Or, the palm touch condition may be changedaccording to the user's setting. In the latter case, the set palm touchcondition may be stored in the memory 600.

The palm touch condition may include, for example, a condition of atleast one of the touch shape, touch area and touch pressure. This isjust an example. The palm touch condition may have another condition inaccordance with the type of the touch sensor panel 100. When a shapesimilar to a hand knife touches the touch sensor panel 100, it can bedetermined that the touch is the palm touch. For example, when anelliptical shape of which the major and minor axes have a predeterminedratio or a half-moon shape touches the touch sensor panel 100, it can bedetermined that the touch is the palm touch. Also, for example, when atouch exceeds the range of the touch area and/or touch pressure whichcan be obtained by the diameter of the object touching the touch sensorpanel 100, it can be determined that the touch is the palm touch.Therefore, a valid touch having a touch area and/or touch pressure whichis greater than a first reference area and/or a first reference pressurecan be detected as a palm touch. Here, in the case of the capacitivetype touch sensor panel 100, the touch area can be calculated as thenumber of sensing cells in which the capacitance change amount is causedby one touch. Or, the touch pressure can be calculated as the sum of thecapacitance change amounts of all of the sensing cells in which thecapacitance is changed by one touch. Here, the first reference areaand/or the first reference pressure may be set differently according tothe object to be used.

When the stylus pen 10 is used as the object, the touch on the touchsensor panel 100 with an object like the finger 20 or palm other thanthe stylus pen 10 should be removed. In this case, the first referencearea and/or the first reference pressure may be set as a valuesufficient to distinguish a touch by the stylus pen 10 from a touch bythe finger.

When the finger 20 is used as the object, the touch by the palm otherthan the finger 20 should be removed. In this case, the first referencearea and/or the first reference pressure may be set as a valuesufficient to distinguish the finger 20 from the palm.

In the foregoing, it has been assumed that the diameter of the styluspen 10 is less than that of the finger 20. Accordingly, when the finger20 is used instead of the stylus pen 10, the first reference area and/orthe first reference pressure may be set as a greater value.

Also, since the user can use any object and the thickness of user'sfinger depends on the gender and age of the user, the embodiment of thepresent invention can be configured to allow the user to set the firstreference area and/or the first reference pressure in accordance withthe diameter of an object to be used. Or, the embodiment of the presentinvention can be configured to allow the apparatus 1000 to set theappropriate first reference area and/or the appropriate first referencepressure by at least one trial touch using the object.

According to the method for removing the palm touch in accordance withthe embodiment of the present invention, even when a passive stylus peninstead of an active stylus pen is used as the object, the touch by theobject like a hand other than the stylus pen can be effectively removed.Also, even when any object is used for the touch, a touch by an objectother than the object can be effectively removed.

The palm touch detected by the above-described detecting the palm touch(S842) should be prevented from being displayed on the display unit 300.

The method for identifying and removing the palm touch in accordancewith the embodiment of the present invention may further includefiltering the palm touch (S843). The filtering the palm touch (S843) mayinclude determining that the detected palm touch and all of the validtouches which are detected in a first region including the touch regionof the palm touch during a first time period before a point of time whenthe palm touch has occurred are included in the palm touch group. Thatis, in the embodiment of the present invention, the backward tracking isperformed during a previous predetermined time period until the point oftime when the palm touch has been detected, so that the touch on thecorresponding region is included in the palm touch group and is notdisplayed on the display unit 300.

The backward tracking method according to the embodiment of the presentinvention is shown and described in (a) of FIG. 5. A touch sequence isshown in (a) of FIG. 5. A touch by the valid touch, release of the touchor the like may sequentially occur. Before the palm touch is detected,all touches may be recognized as a valid touch and processed. Here, whenthe touch of the third block is detected as a palm touch, the secondprocessing unit 520 tracks backward the first time period T_(BT) fromthe time when the palm touch has been detected. Here, during thecorresponding first time period T_(BT), all touches recognized as avalid touch may be classified into the palm touch group.

This is because the valid touch which is not recognized as a palm touchfrequently occurs before the palm touch occurs. Palm has a curvedsurface. Therefore, when the palm touches the touch sensor panel 100, itis common that the palm does not touch at a time an area correspondingto the palm touch. Unless the backward tracking method according to theembodiment of the present invention is applied, when a touch as apre-action for the palm touch on the touch sensor panel 100 occurs priorto the occurrence of the palm touch and the touch does not have a regionwide enough to be determined as a palm touch, the touch may be displayedas a valid touch on the display unit 300. Therefore, through use of thebackward tracking method according to the embodiment of the presentinvention, the above-described problem can be overcome. For example,although a first touch in FIG. 5 is detected as a valid touch first, thefirst touch is within the backward tracking time period according to thepalm touch detection. Therefore, the first touch may be classified intothe palm touch group. Accordingly, the input by the first touch can beprevented from being displayed on the display unit 300.

Here, the first time period T_(BT) during which the backward tracking isperformed at the time of occurrence of the palm touch can be generallydetermined by using statistical data of a time period from a point oftime when the palm touches the touch sensor panel 100 to a point of timewhen the touch is determined as the palm touch. For example, since thewriting habit, hand size, touch portion and direction between the handand the touch sensor panel 100, etc., are various according toindividual, the first time period T_(BT) can be adaptively set byconsidering them. Also, the first time period T_(BT) may be set by theuser or may be set as a default value stored in the memory 600. Also,the first time period T_(BT) may be set according to the capability ofthe structure within the apparatus 1000 including the touch sensor panel100, which supports the above-described algorithm. For example, thefirst time period T_(BT) may be limited according to the capability ofthe memory.

Here, the touch which is classified into the palm touch group may beintended to deal with a touch located within the first region includingthe region of the touch detected as a palm touch. For example, the firstregion may be within a first distance “d” from the edge of the touchregion of the palm touch or may be within a second distance “D” from thecenter of the touch region of the palm touch. Or, the first region maybe a times as large as the touch region of the palm touch. Here, thevalue of a is a scale factor and may be a rational number having a valuegreater than 1. Here, the distance “D” from the center of the touchregion of the palm touch can be applied when the touch region of thepalm touch has a shape such as a circle. For example, the touch regionof the palm touch may have a circular shape, an elliptical shape, ahalf-moon shape, or any shape satisfying a predetermined condition.

Referring to FIG. 1, the touch region of the palm touch is indicatedwith a dotted circle by a reference numeral 21. This is just an example.The touch region of the palm touch may have any shape obtained bytouching the touch sensor panel 100 with the palm. Here, the touch whichcan be classified into the palm touch group may occur in a larger regionincluding the region indicated by the reference numeral 21. For example,the entire region within the first distance “d” from the edge of thepalm touch region 21, or the entire region within the second distance“D” from the center of the palm touch region 21 may be classified intothe palm touch group. Here, the first region 22 may be a times largerthan the palm touch region 21.

This is because when a touch by a portion of the hand is the palm touch,a touch which occurs at the same time or at different times with thepalm touch may occur by another portion of the hand. For example, whenthe palm touch is caused by a portion of the palm, it is highly probablethat a touch by the finger, etc., which has not been determined as apalm touch, occurs at the same time with the palm touch or prior to theoccurrence of the touch. Therefore, in the embodiment of the presentinvention, it is possible that a touch on a region wider than the palmtouch region is included in the palm touch group and is removed.

Here, the first or second distance may be preset as a value greater than0 according to the user's selection or a default value. Also, the scalefactor α may be preset as a value greater than 1 according to the user'sselection or a default value. When the user sets the first distance “d”,the second distance “D” or the scale factor α, the user may consider thediameter of the object, user's hand size, user's habit of holding theobject, etc. Or, an appropriate value can be set by default from theuser's touch information collected by the apparatus 1000. This value maybe stored in the memory 600.

When the palm touch group is classified by the backward tracking method,S850 may be performed from S843 as an arrow “a” indicates in FIG. 2.That is, the input which is detected in S820 and corresponds to thevalid touch is displayed on the display unit 300 in S830. Since thetouch which has been already detected as a valid touch through thebackward tracking method is classified into the palm touch group in thefuture, deleting the input corresponding to the valid touch which isincluded in the palm touch group among the inputs already displayed onthe display unit 300 (S850) may be performed.

This signifies a case where the touch on the touch sensor panel 100 isdisplayed on the display unit 300 in real time. In a case where thetouch occurs on the touch sensor panel 100 at different times with thedisplay on the display unit 300, S830 may be performed as indicated byan arrow “b”. Here, in S830, only the input corresponding to the validtouch other than the valid touches classified into the palm touch groupby the backward tracking method among the detected valid touches can bedisplayed on the display unit 300. This case corresponds to S830 and themethod for removing the palm touch may be completed.

The filtering the palm touch (S843) may include determining that allvalid touches which are detected within a second region including thetouch region 21 of the palm touch from a point of time when the touchdetermined as a palm touch is released until a second time period T_(FT)elapses are classified into the palm touch group. In other words, in theembodiment of the present invention, a forward tracking method isperformed from a point of time when the palm touch is released until theelapse of a predetermined point of time, and then all touches on thecorresponding region are included in the palm touch group and can beprevented from being displayed on the display unit 300.

The forward tracking method according to the embodiment of the presentinvention is shown and described in (b) of FIG. 5. A touch sequence isshown in (b) of FIG. 5. The forward tracking method according to theembodiment of the present invention can be performed from a time pointwhen the touch determined as a palm touch is released. In the embodimentof the present invention, a touch occurring during the second timeperiod TFT after the time point that the palm touch is released isignored and can be prevented from being displayed on the display unit300.

This is because, even after the palm touch is released, an error mayoccur due to the curved surface or elasticity of the hand, or acapacitance change of the touch sensor panel 100, which is caused by thetemperature of the hand. For example, when the palm is released from thetouch sensor panel 100, the touch area is gradually reduced, and thus,jittering may occur which causes the touch to be recognized as a validtouch without being recognized as a palm touch. Also, according to theembodiment of the present invention, when hovering which is not a directtouch on the touch sensor panel 100 is included in the valid touch, theabove-described jittering may be more problematic.

As long as the forward tracking method is not applied to the controlmethod and the control device 800 for the touch sensor panel 100according to the embodiment of the present invention, when a portion ofthe hand still touches the touch sensor panel 100 during the release ofthe palm so as to release the palm touch, there may occur a problem thatthe touch is displayed as a valid touch on the display unit 300.Therefore, the embodiment of the present invention can solve theaforementioned problem by using the forward tracking method. In otherwords, according to the embodiment of the present invention, a touch onthe corresponding region during the second time period T_(FT) after thepalm touch is released is ignored and can be prevented from beingdisplayed on the display unit 300.

Here, the second time period T_(FT) during which the forward trackingmethod is performed may be generally determined by using statistics ofthe time period from a point of time when the palm touch is released toa point of time when the palm is completely separated from the touchsensor panel 100. Also, the second time period T_(FT) may be set by theuser or may be set as a default value stored in memory 600. Thedescription of the first time period T_(FT) can be applied in the samemanner to the setting of the second time period T_(FT).

Here, the touch which is classified into the palm touch group may beintended to deal with a touch located within the second region includingthe region of the touch detected as a palm touch. Here, since thedescription of the second region is the same as that of the firstregion, the repetitive descriptions thereof will be omitted hereafter.Also, a third distance may correspond to the aforementioned firstdistance “d”, and a fourth distance may correspond to the aforementionedsecond distance “D”. However, this is just an example. Depending on theembodiment, the third distance may be set to be different from the firstdistance “d”, and the fourth distance may be also set to be differentfrom the second distance “D”.

When the palm touch group is classified by the forward tracking method,S830 may be performed from S843 as an arrow “b” indicates in FIG. 2.That is, when the input which is detected in S820 and corresponds to thevalid touch is displayed on the display unit 300 in S830, the input bythe valid touch classified into the palm touch group through the forwardtracking method can be controlled not to be displayed on the displayunit 300.

Also, depending on the embodiment, when a long time is required forclassifying into the palm touch group S840 or the result cannot bereflected in S830 in real time for a particular reason, S850 may beperformed as the arrow “a” indicates. That is, the input correspondingto the valid touch detected in S820 is displayed on the display unit 300in S830. Subsequently, S850 in which the input corresponding to thevalid touch classified into the palm touch group by the forward trackingmethod is deleted on the display unit 300 may be performed.

Although FIG. 3 and the present specification show that the processor500 is divided into the first processing unit 510 and the secondprocessing unit 520, this is just an example. S820 in which the validtouch is detected and S840 in which the valid touch which is included inthe palm touch group is determined can be all performed withoutdistinction by one processor 500.

As described above, by applying the method for identifying/removing thepalm touch in the control method and the control device 800 for thetouch sensor panel 100 according to the embodiment of the presentinvention, the user is allowed to place his/her hand holding the objecton the touch sensor panel 100 and perform a work, thereby reducing thefatigue of the hand and improving the operation accuracy of the touchsensor panel 100.

Also, by applying the method for identifying/removing the palm touch inthe control method and the control device 800 for the touch sensor panel100 according to the embodiment of the present invention, not only thetouch determined as a palm touch, but a touch action related to the palmtouch prior to or posterior to the palm touch is included in the palmtouch group and is removed together with the palm touch, so thatunintended touches of the user can be effectively reduced.

Although embodiments of the present invention were described above,these are just examples and do not limit the present invention. Further,the present invention may be changed and modified in various ways,without departing from the essential features of the present invention,by those skilled in the art. For example, the components described indetail in the embodiments of the present invention may be modified.Further, differences due to the modification and application should beconstrued as being included in the scope and spirit of the presentinvention, which is described in the accompanying claims.

What is claimed is:
 1. A control method for a touch sensor panel, themethod comprising: obtaining touch information on the touch sensor panelfrom which an electrical signal outputted is changed according to atouch; detecting at least one valid touch from the touch information;determining that a valid touch of the at least one valid touch isincluded in a palm touch group by (a) detecting a palm touch, whichmeets a palm touch condition, among the at least one valid touch, and(b) determining all valid touches from a detection time of the palmtouch to a predetermined backward tracking time; and non-displaying, ona display unit, the valid touch included in the palm touch group.
 2. Themethod of claim 1, wherein the determining the valid touch is includedin the palm touch group comprises: determining a first region includinga touch region of the palm touch as the palm touch group, wherein thefirst region is within a first distance from the edge of the touchregion of the palm touch or is within a second distance from the centerof the touch region of the palm touch, and wherein the first or seconddistance is preset as a value greater than 0 according to a user'sselection or a default value.
 3. The method of claim 1, furthercomprising: displaying, on the display unit, an input corresponding toeach of the at least one valid touch other than the valid touch includedin the palm touch group.
 4. The method of claim 1, wherein the at leastone valid touch includes hovering on the touch sensor panel.
 5. Themethod of claim 1, further comprising storing the at least one validtouch in a memory according to a touch order.
 6. The method of claim 1,wherein the palm touch condition comprises a condition of at least oneof a touch area and a touch pressure.
 7. A control device of a touchsensor panel, the control device comprising: a touch informationdetector which obtains touch information on the touch sensor panel fromwhich an electrical signal outputted is changed according to a touch;and a processor which detects at least one valid touch from the touchinformation and determines that a valid touch of the at least one validtouch is included in a palm touch group by (a) detecting a palm touch,which meets a palm touch condition, among the at least one valid touch,and (b) determining all valid touches from a detection time of the palmtouch to a predetermined backward tracking time, wherein the processorcontrols a display unit not to display the valid touch included in thepalm touch group.
 8. The control device of claim 7, wherein theprocessor comprises: determining a first region including a touch regionof the palm touch as the palm touch group, wherein the first region iswithin a first distance from the edge of the touch region of the palmtouch or is within a second distance from the center of the touch regionof the palm touch, and wherein the first or second distance is preset asa value greater than 0 according to a user's selection or a defaultvalue.
 9. The control device of a touch sensor panel of claim 7,wherein, the processor causes the display unit to display an inputcorresponding to each of the at least one valid touch other than thevalid touch included in the palm touch group.
 10. The control device ofclaim 7, wherein the at least one valid touch includes hovering on thetouch sensor panel.
 11. The control device of claim 7, furthercomprising a memory in which the at least one valid touch is storedaccording to a touch order.
 12. The control device of claim 7, whereinthe palm touch condition comprises a condition of at least one of atouch area and a touch pressure.
 13. A control method for a touch sensorpanel, the method comprising: obtaining touch information on the touchsensor panel from which an electrical signal outputted is changedaccording to a touch; detecting at least one valid touch from the touchinformation; determining that a valid touch of the at least one validtouch is included in a palm touch group by (a) detecting a palm touch,which meets a palm touch condition, among the at least one valid touch,and (b) determining a larger region wider than a palm touch region asthe palm touch group, wherein the palm touch region is defined by thepalm touch, wherein the determining the valid touch is included in thepalm touch group comprises determining all valid touches from adetection time of the palm touch to a predetermined backward trackingtime; and non-displaying, on a display unit, the valid touch included inthe palm touch group.
 14. The method of claim 13, wherein the largerregion is within a first distance from the edge of the palm touch regionor is within a second distance from the center of the palm touch region,and wherein the first or second distance is preset as a value greaterthan 0 according to a user's selection or a default value.
 15. Themethod of claim 13, wherein the determining the valid touch is includedin the palm touch group comprises: determining all valid touches from adetection time of the palm touch to a predetermined forward trackingtime.
 16. A control device of a touch sensor panel, the control devicecomprising: a touch information detector which obtains touch informationon the touch sensor panel from which an electrical signal outputted ischanged according to a touch; and a processor which detects at least onevalid touch from the touch information and determines that a valid touchof the at least one valid touch is included in a palm touch group by (a)detecting a palm touch, which meets a palm touch condition, among the atleast one valid touch, and (b) determining a larger region wider than apalm touch region as the palm touch group, wherein the palm touch regionis defined by the palm touch, wherein the processor determines all validtouches from a detection time of the palm touch to a predeterminedbackward tracking time, and wherein the processor controls a displayunit not to display the valid touch included in the palm touch group.17. The method of claim 16, wherein the larger region is within a firstdistance from the edge of the palm touch region or is within a seconddistance from the center of the palm touch region, and wherein the firstor second distance is preset as a value greater than 0 according to auser's selection or a default value.
 18. The method of claim 16, whereinthe processor determines all valid touches from a detection time of thepalm touch to a predetermined forward tracking time.